In recent years, in transmission systems, the number of users aggregating on stations and the amount of data in communication are in an increasing trend together with widespread use of smartphones and so forth and diversification of services using the Internet. A transmission apparatus for use with a transmission system identifies the priority degree in response to a data type and executes a data process in response to the priority degree, for example, in order to simultaneously process various data of sound whose data delay is not permitted or mails whose data delay is permitted to some degree.
In a transmission apparatus, high speed processing of data may be demanded. A data plane process such as flow identification, destination search, quality of service (QoS) control and so forth of a packet is implemented by hardware such as, a field programmable gate array (FPGA). Further, in recent years, together with improvement of central processing unit (CPU) performances, attention is paid to network functions virtualization (NFV) that makes network design and construction flexible by executing network functions on a general-purpose server. However, it is realistically difficult as yet to perform packet processing, for example, exceeding 100 Gbps fully by software. Therefore, in recent years, also it is investigated to implement, in a transmission apparatus, a scheduler function for controlling an output amount of packets based on a contract area or a priority degree by software while, for example, inputting and outputting functions for each packet are implemented by hardware.
FIG. 29 is an explanatory view depicting an example of a shaping function in a conventional transmission apparatus. A transmission apparatus 200 may include an input processing unit 201, a queue management unit 202, an output processing unit 203 and a scheduler 204. The input processing unit 201 may be a processing unit that identifies an input flow. The queue management unit 202 may manage a plurality of queues 202A and a plurality of shaper 202B. Each queue 202A may store one or more input flows for each flow identifier (ID). Each shaper 202B may be disposed individually for a queue 202A and shape and output an input flow stored in the queue 202A. The output processing unit 203 may output a shaped and outputted flow. The scheduler 204 may provide a fixed readout allowable amount (credit) to each of the plurality of queues 202A. The queue management unit 202 may read out, from the plurality of queues 202A, one or more packets consuming the readout allowable amount (credit) in an order in which readout conditions relating to the readout allowable amount (credit) for each queue 202A and the data amount of one or more packets accumulated for each queue 202A are satisfied.
In the transmission apparatus 200, for example, the input processing unit 201, the queue management unit 202 and the output processing unit 203 may be configured from hardware, and the scheduler 204 may be configured from software. According to the transmission apparatus 200, while implementation of given functions by hardware may be achieved, improvement of functions of the scheduler 204 by software may be achieved.
Examples of related art include disclosed in Japanese Laid-Open Patent Application No. 2014-135581, Japanese Laid-Open Patent Application No. 2015-19369, Japanese Laid-Open Patent Application No. 2015-109672, Japanese Laid-Open Patent Application No. 2015-91061 or Japanese National Publication of International Patent Application No. 2005-510893.